USN-1308-1: bzip2 vulnerability

Details

vladz discovered that executables compressed by bzexe insecurely create
temporary files when they are ran. A local attacker could exploit this issue to
execute arbitrary code as the user running a compressed executable.

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 8.04

• bzip2 - 1.0.4-2ubuntu4.2

Ubuntu 11.10

• bzip2 - 1.0.5-6ubuntu1.11.10.1

Ubuntu 11.04

• bzip2 - 1.0.5-6ubuntu1.11.04.1

Ubuntu 10.10

• bzip2 - 1.0.5-4ubuntu1.1

Ubuntu 10.04

• bzip2 - 1.0.5-4ubuntu0.2

In general, a standard system update will make all the necessary changes to
the bzexe utility. If you have previously used bzexe to compress any
executables, they need to be recompressed using the updated version.

References

• CVE-2011-4089